An organism has 3 duplicated chromosomes after the S phase of the Cell Cycle, the total sister chromatids have - 6 chromatids.
The number of Chromatids doubles in the Synthesis phase, but the number of chromosomes stays the same. Anaphase doubles the chromosome number but does not affect the chromatid number
The chromosome is different at different times in the cell cycle, depending upon whether the DNA has replicated or not, and when the sister chromatids separate
Learn more about the S-phase:
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